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arXiv · 1507.06229

Dipolar Capillary Interactions between Tilted Ellipsoidal Particles Adsorbed at Fluid-Fluid Interfaces

Gary B. Davies·Lorenzo Botto
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Abstract

Capillary interactions have emerged as a tool for the directed assembly of particles adsorbed at fluid-fluid interfaces, and play a role in controlling the mechanical properties of emulsions and foams. In this paper, following Davies et al. [Advanced Materials, 26, 6715 (2014)] investigation into the assembly of ellipsoidal particles at interfaces interacting via dipolar capillary interactions, we numerically investigate the interaction between tilted ellipsoidal particles adsorbed at a fluid-fluid interface as their aspect ratio, tilt angle, bond angle, and separation vary. High-resolution Surface Evolver simulations of ellipsoidal particle pairs in contact reveal an energy barrier between a metastable tip-tip configuration and a stable side-side configuration. The side-side configuration is the global energy minimum for all parameters we investigated. Lattice Boltzmann simulations of clusters of up to 12 ellipsoidal particles show novel highly symmetric flower-like and ring-like arrangements.

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Gary B. Davies, Lorenzo Botto. 2015-07-22. Dipolar Capillary Interactions between Tilted Ellipsoidal Particles Adsorbed at Fluid-Fluid Interfaces. https://arxiv.org/abs/1507.06229

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